I've said it before and I'll say it again, US-40 through Colorado is an amazing road. Breathtaking at every bend, hill, dip, and whatever. Route 40 will take you to near Rabbit Ears Pass, through Steamboat Springs, across the Continental Divide a couple of times, and Dinosaur, Co where Dinosaur National Monument is.

There are a lot of routes through Colorado that are this way, though, so basically take your pick :)